So what: The stock has soared over the past year on better-than-expected growth, and today's second-quarter results -- EPS spiked 70% on a 22% jump in revenue -- coupled with upbeat guidance for the full year only reinforces that trend.In fact, gross margin expanded 40 basis points to 41.3% while same-store sales increased 15%, giving analysts plenty of good vibes over its competitive position and ability to grow profitably.

Now what: Management now sees full-year EPS of $2.45 to $2.60 on revenue of $940 million to $963 million, up nicely from its prior view of $2.10 to $2.35 and $913 million to $942 million. "Our success in expanding gross margin allows us to reinvest across our industry-leading value proposition, and we see multi-year opportunities to expand operating margin while we continue to grow our store base," said CEO Robert Lynch. Of course, with the stock now up a whopping 160% over its 52-week lows and trading at a forward P/E of about 30, I'd wait for some of the excitement to fade before buying into those growth prospects.